A new endemic species, Eranthis tanhoensissp. nov., is described from the Republic of Buryatia and Irkutsk Province, Russia. It belongs to Eranthis section Shibateranthis and is morphologically similar to E. sibirica and E. stellata. An integrative taxonomic approach, based on cytogenetical, molecular and biochemical analyses, along with morphological data, was used to delimit this new species.
Finding morphological differences between cytotypes that are stable throughout their geographical range is important for understanding evolution of polyploid complexes. The ancient monocot lineage Acorus includes two groups, of which A. calamus s.l., an important medicinal plant, is a polyploid complex with a centre of diversity in Asia. European plants are sterile triploids introduced by humans. An early study suggested that plants from temperate Asia are tetraploids, but subsequent work revealed diploids and triploids rather than tetraploids in Asiatic Russia; however, cytotype diversity in Western Siberia is insufficiently known. We document the occurrence of diploids and triploids in Western Siberia. Triploids that do not differ in genome size from European Acorus are abundant in the valley of the river Ob where the ability for extensive vegetative propagation provides ecological advantages. An isolated population of aneuploid triploids with 33 chromosomes is found outside the Ob valley. Flow cytometry provides an efficient tool for identification of aneuploid plants in Acorus. All triploids are sterile, but their flowers develop uniform parthenocarpic fruits. Fruits of diploids usually vary in size within a spadix depending on the number of developing seeds. In contrast to North America, where the native diploid plants differ from the introduced triploids by the absence of a secondary midrib of the ensiform leaf blade, Siberian diploids are similar to triploids in possessing a secondary midrib. We confirm that diploids differ from triploids in the size of air lacunae in leaves, which is determined by cell number rather than cell size in septa of aerenchyma. A combination of spathe width and spadix length measured after the male stage of anthesis shows different (slightly overlapping) patterns of variation between diploids and triploids in our material.
Genome editing has become one of the key technologies for plant breeding. However, in polyploid species such as chrysanthemum, knockout of all loci of multiple genes is needed to eliminate functional redundancies. We identified six cDNAs for the CmDMC1 genes involved in meiotic homologous recombination in chrysanthemum. Since all six cDNAs harbored a homologous core region, simultaneous knockout via TALEN-mediated genome editing should be possible. We isolated the CmDMC1 loci corresponding to the six cDNAs and constructed a TALEN-expression vector bearing a CmDMC1 target site containing the homologous core region. After transforming two chrysanthemum cultivars with the TALEN-expression vector, seven lines exhibited disruption of all six CmDMC1 loci at the target site as well as stable male and female sterility at 10–30 °C. This strategy to produce completely sterile plants could be widely applicable to prevent the risk of transgene flow from transgenic plants to their wild relatives.
In the living Allium collection of the South Siberian Botanical Garden of the Altai State University, Barnaul (Russia), among the species Allium tulipifolium and A. robustum (A. subg. Melanocrommyum sect. Decipientia), several morphologically intermediate plants grown from seeds were found. We assumed they could result from spontaneous hybridization. To confirm our assumption we studied the hybrids and their alleged parents cytologically (chromosome and genome size) and compared the sequences of the nuclear DNA (ITS) and three plastid DNA fragments (trnL-trnF and rpl32-trnL spacers and rps16 intron). Our data confirmed the hybrid nature of these plants and also showed that the hybridization between the two species (A. tulipifolium and A. robustum) is possible in both directions. This opens up opportunities for targeted hybridization and breeding of new ornamental varieties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.